Balanced driving head for machines



Jan. 7, 1936.

F. F. JOHNSON 2,027,174

- BALANCED DRIVING HEAD FOR MACHINES Filed April 16, 19:54

INVENTOR ATTO RNEYS UNITED STATES PATENT OFFICE 2,027,174 BALANCED DRIVING HEAD FOR MACHINES This invention relates Forrest F. Johnson, Spencer,

The Spencer Manufacturing 00.,

a corporation of Ohio Ohio, assignor to Spencer, Ohio,

Application April 16, 1934, Serial No. 720,836

3Claims.

to driving heads for machines and has for its object to provide a head which will provide a on Work while turning, the like.

balanced driving torque grinding, hobbing and Conventional machines of this type employ a work center for supporting one end of the work and a driving dog having a single driving contact. The result is that the work tends to flex and then to ride upon the cutting tool producing an imperfect cut.

It is therefore the primary object of this invention to provide a plurality of driving means in the form of pins, and

to so arrange and support the pins that an equal driving pressure is had from diametrically opposite points.

Other objects and advantages will become hereinafter more fully apparent as reference is had to the accompanying drawing wherein my invention is illustrated b in whichy way of example and Figure 1 is a side elevation of a machine equipped with my improved driving head;

Fig. 2 is a front elevation of the head taken along the line 2-2 'of Fig. 1, and

Fig. 3 is a transverse section taken axially of the head taken along the line 3-3 of Fi 2.

More particularly, l indicates a machine generally, invention may of a conventional type upon which my be suitably employed. The machine includes the conventional bed 2, tailstock 3, pulleys 4,

spindle 5, face plate 6 and work center 1. Secured to the face plate 6 is a base plate 8 having journals 9 carried by projections outstanding from said base plate.

These journals may suitably be adjustable screws having conical or ball ends for r in a fork member eception by depressions ID. This member Ill has two arms or pins II which rock on the journals 9 as will be hereinafter explained.

[2 refers to a driving .dog having two tails l3 and II. This dog has the conventional adjustable jaws [5 for grasping the work 16 which is supported by and between the work center 1 and the tailstock of Figure 2 will show 3, for rotation. An inspection 1 that if the dog be shifted, say, to the left from the position shown,

only

one pin ll would contact the tails of the dog unless the pins be rockably mounted. However,

the rocking of the pins alters the angular distance between the points of contact of the pins to compensate and to balance the driving pressures on the tails. The result is that contacts diametrically opposite with respect to the work center drive the dog l2 and hence the work Is. 5

Various modifications may be made to adapt the principles herein involved to various machines and I therefore desire my protection to extend as defined by the appended claims.

What I claim is: 10

1. In a driving head for machines, a face plate, a work center secured in said plate, a driving dog for work supported by the work adjacent said center, said dog having a plurality of driving tails, anda floating connection between said face 15 plate and said tails comprising driving pins normal to the surface of said plate and journalled thereon for rocking with respect to said plate in finding a driving contact with said tails, and means for adjusting the journals of said pins 0 radially of said face plate.

2. In a driving head for machines, a face plate, a work center secured in said face plate, a driving dog for work supported by the work adjacent said center, said dog having a plurality of driv- 25 ing tails, a fork member rockably supported from said face plate at points diametrically spaced with respect to said work center, the arms of said fork member extending outwardly from said face plate, journals on said face 30 plate for said fork member at points adjacent said arms comprising radially adjustable screws having conical ends, said arms being rockable in said journals to find a driving contact with said tails, means for shifting said journals radially of the work and means for shifting said tails laterally of said journals.

3. In a driving head for machines, a face plate, a base plate secured to said face plate and having projections therefrom, a fork arm journalled in said projections and having arms paralleling the axis of said plates in free rocking engagement therewith, a work center, a piece of work in said center, a two tailed dog rigid with said work and adapted for driving contact by said 45 arms, said arms being radially adjustable on said base plate, said dog being radially adjustable on said work.

FORREST F. JOHNSON. 

